Search results for: tool comparison

Authors: Arya Pirooz

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The effects of different fuels (DME, RME B100, and SME B100) on barrel engines were studied as a general, single dimensional investigation for characterization of these types of engines. A base computational model was created as reference point to be used as a point of comparison with different cases. The models were computed using the commercial computational fluid dynamics program, Diesel-RK. The base model was created using basic dimensions of the PAMAR-3 engine with inline unit injectors. Four fuel cases were considered. Optimized models were also considered for diesel and DME cases with respect to injection duration, fuel, injection timing, exhaust and intake port opening, CR, angular offset. These factors were optimized for highest BMEP, combined PM and NOx emissions, and highest SFC. Results included mechanical efficiency (eta_m), efficiency and power, emission characteristics, combustion characteristics. DME proved to have the highest performing characteristics in relation to diesel and RME fuels for this type of barrel engine.

Keywords: DME, RME, Diesel-RK, characterization, inline unit injector

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Authors: Ahmad K. Samaila, Basant K. Jha

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This paper presents the effects of suction/injection of transient/steady natural convection flow of reactive viscous fluid in a vertical porous pipe. The mathematical model capturing the time dependent flow of viscous reactive fluid is solved using implicit finite difference method while the corresponding steady state model is solved using regular perturbation technique. Results of analytical and numerical solutions are reported for various parametric conditions to illustrate special features of the solutions. The coefficient of skin friction and rate of heat transfer are obtained and illustrated graphically. The numerical solution is shown to be in excellent agreement with the closed form analytical solution. It is interesting to note that time required to reach steady state is higher in case of injection in comparison to suction.

Keywords: porous pipe, reactive viscous fluid, transient natural-convective flow, analytical solution

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Authors: Nana Weng

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Firstly, based on two diamond models and Value-Rarity-Inimitability-Organization framework, this paper analyzes the Country Specific factors of and firm specific factors which influence subsidiaries’ sustainable competitive advantage. Then, according to the main content of Strategic Human Resource Management (SHRM) research that HRM strategy should fit into corporate strategy, we explained what the SHRM practices should be in the context of localization strategies within Multinational Enterprise (MNE) companies. Then we choose two Japanese MNE subsidiaries in the same industry and tested the hypothesis that localization SHRM practices positively impact on subsidiary’s sustainable competitive advantage, further positively affect firm integrated performance (both financial performance and organizational and organizational performance) lever through High Performance Work Practices (HPWPs) of local employees.

Keywords: localization SHRM, firm integrated performance, Japanese MNE subsidiaries, Vietnam

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Authors: Sabita Mahapatra

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‘Going green’ has been an emerging issue worldwide driving companies to continuously enhance their green capabilities and implement innovative green practices to protect the environment and improve business performance. Green has become a contemporary business environmental issue. The resource advantage theory is adopted in the present study to observe the impact of marketing orientation and green innovation practices on environmental and firm’s performance. The small and medium firms compared to large firms have different approach towards market orientation as a strategic tool. The present study proposes a conceptual framework regarding the impact of market orientation on environmental and firm’s performance through green innovation practices in the context of small and medium scale industries (SMEs). The propositions developed in the present paper would provide scope for future research study to validate the conceptual framework in the emerging economy like India.

Keywords: market orientation, green innovation practices, environment performance, corporate performance, emerging market

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Authors: Sai On Cheung, Qiuwen Ma, Fong Chung Lee

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Due to increased project complexity and technological advancement in the last decade, the designers and contractors are expected to put more efforts to achieve project goals. To render extra efforts from the agents, incentivization has become one of the primary strategies for the client. Despite increased academia interest in the design of incentive strategies, there is still a need for discussion about the underlying motivations and favourable conditions to make incentives effective. Therefore, this study focuses on the effects of motivations and favourable conditions for the use of incentives in public projects. Questionnaire survey is used as the data collection tool. The questionnaire survey was piloted through interviews with professionals from Hong Kong public sector. A total of 100 responses were collected for this survey. Accountability and organizational effectiveness were found to be the prime objectives of incentives installed by public clients. Furthermore, a list of favourable conditions for incentivization and its consequent effects on cost, schedule, risk and public opinions were identified. To conclude, this study analyses the means and ends of the use of incentives in public projects in Hong Kong.

Keywords: incentives, public accountability, project effectiveness, public opinions

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Authors: Chutikarn Sriviboon

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The objectives of this research were to study the operation of the Labor Fund and to investigate the needs for money and assistance from Thai laborers both from within the system and out of the system and to compare between the assistance from domestic and international funds. The population of this study included three labor groups: group one was laborer in the system who were the members of saving cooperative, group two was laborer in the system who were not the members of saving cooperative, and group three was laborer who were not in the system. This was a mixed research of quantitative and qualitative methods. The findings can be categorized into four parts. First, the labor fund was beneficial to Thai laborers by giving access to government funds but the weakness was found to be poor public relations. Second, the labor funds should extend their assistance to laborer in the system who was not the members of saving cooperative. Third, the comparison between domestic labor funds and international labor funds revealed that there were no international funds which provided assistance the same way as Thai labor funds. Finally, there was a need to improve the management of labor funds and to provide long term assistance to Thai labors.

Keywords: effectiveness, quality, labor funds, service

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Authors: Palwinder Singh, Munish Sandhir, Tejinder Singh

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The ordinary differential equations (ODE) represent a natural framework for mathematical modeling of many real-life situations in the field of engineering, control systems, physics, chemistry and astronomy etc. Such type of differential equations can be solved by analytical methods or by numerical methods. If the solution is calculated using analytical methods, it is done through calculus theories, and thus requires a longer time to solve. In this paper, we compare the numerical accuracy of the solutions given by the three main types of one-step initial value solvers: Taylor’s Series Method, Euler’s Method and Runge-Kutta Fourth Order Method (RK4). The comparison of accuracy is obtained through comparing the solutions of ordinary differential equation given by these three methods. Furthermore, to verify the accuracy; we compare these numerical solutions with the exact solutions.

Keywords: Ordinary differential equations (ODE), Taylor’s Series Method, Euler’s Method, Runge-Kutta Fourth Order Method

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Authors: Jorge Gonzalez Camus, Valentin Keyantuo, Mahamadi Warma

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In this work, we obtain representation results for solutions of a time-fractional differential equation involving the discrete fractional Laplace operator in terms of generalized Wright functions. Such equations arise in the modeling of many physical systems, for example, chain processes in chemistry and radioactivity. The focus is on the linear problem of the simplified Moore - Gibson - Thompson equation, where the discrete fractional Laplacian and the Caputo fractional derivate of order on (0,2] are involved. As a particular case, we obtain the explicit solution for the discrete heat equation and discrete wave equation. Furthermore, we show the explicit solution for the equation involving the perturbed Laplacian by the identity operator. The main tool for obtaining the explicit solution are the Laplace and discrete Fourier transforms, and Stirling's formula. The methodology mainly is to apply both transforms in the equation, to find the inverse of each transform, and to prove that this solution is well defined, using Stirling´s formula.

Keywords: discrete fractional Laplacian, explicit representation of solutions, fractional heat and wave equations, fundamental

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Authors: Negar Vkilbashi, Hassan Kabiri

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Modern diplomacy, in its general form, refers to the people and not the governments, and diplomacy tactics are more addressed to the people than to the governments. Media diplomacy and cyber diplomacy are also one of the sub-branches of public diplomacy and, in fact, the role of media in the process of influencing public opinion and directing foreign policy. Mass media, including written, radio and television, theater, satellite, internet, and news agencies, transmit information and demands. What the Qatari government tried to implement in the countries of the region during the Arab Spring and after was through its important media, Al Jazeera. The embargo on Qatar began in 2017, when Saudi Arabia, the United Arab Emirates, Bahrain, and Egypt imposed a land, sea, and air blockade against the country. The media tool constitutes the cornerstone of soft power in the field of foreign policy, which Qatari leaders have consistently resorted to over the past two decades. Undoubtedly, the role it played in covering the events of the Arab Spring has created geopolitical tensions. The United Arab Emirates and other neighboring countries sometimes criticize Al Jazeera for providing a platform for the Muslim Brotherhood, Hamas, and other Islamists to promote their ideology. In 2011, at the same time as the Arab Spring, Al Jazeera reached the peak of its popularity. Al Jazeera's live coverage of protests in Tunisia, Egypt, Yemen, Libya, and Syria helped create a unified narrative of the Arab Spring, with audiences tuning in every Friday to watch simultaneous protests across the Middle East. Al Jazeera operates in three groups: First, it is a powerful base in the hands of the government so that it can direct and influence Arab public opinion. Therefore, this network has been able to benefit from the unlimited financial support of the Qatar government to promote its desired policies and culture. Second, it has provided an attractive platform for politicians and scientific and intellectual elites, thus attracting their support and defense from the government and its rulers. Third, during the last years of Prince Hamad's reign, the Al Jazeera network formed a deterrent weapon to counter the media and political struggle campaigns. The importance of the research is that this network covers a wide range of people in the Middle East and, therefore, has a high influence on the decision-making of countries. On the other hand, Al Jazeera is influential as a tool of public diplomacy and soft power in Qatar's foreign policy, and by studying it, the results of its effectiveness in the past years can be examined. Using a qualitative method, this research analyzes the impact of the media on the implementation of Qatar's foreign policy on the public opinion of the people of the Middle East. Data collection has been done by the secondary method, that is, reading related books, magazine articles, newspaper reports and articles, and analytical reports of think tanks. The most important findings of the research are that Al Jazeera plays an important role in Qatar's foreign policy in Qatar's public diplomacy. So that, in 2011, 2017 and 2023, it played an important role in Qatar's foreign policy in various crises. Also, the people of Arab countries use Al-Jazeera as their first reference.

Keywords: Al Jazeera, Qatar, media, diplomacy

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Authors: Satyavati Shukla, Lakhan V. Rathod, Mohan V. Khire

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Rapid urbanization changes the land use/land cover pattern of a developing region. Due to these land surface changes, stream flow of the rivers also changes. It is important to investigate the factors affecting hydrological characteristics of the river basin for better river basin management planning. This study is aimed to understand the effect of Land Use/Land Cover (LU/LC) changes on stream flow of Upper Bhima River basin which is highly stressed in terms of water resources. In this study, Upper Bhima River basin is divided into two adjacent sub-watersheds: Mula-Mutha (urbanized) sub-watershed and Bhima (non-urbanized) sub-watershed. First of all, LU/LC changes were estimated over 1980, 2002, and 2009 for both Mula-Mutha and Bhima sub-watersheds. Further, stream flow simulations were done using Soil and Water Assessment Tool (SWAT) for the streams draining both watersheds. Results revealed that stream flow was relatively higher for urbanized sub-watershed. Through Sensitivity Analysis it was observed that out of all the parameters used, base flow was the most sensitive parameter towards LU/LC changes.

Keywords: land use/land cover, remote sensing, stream flow, urbanization

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Authors: M. I. Mohammed, U. M. Ahmad

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Analyses of mineral elements were carried out on some coarse grains used as staple food in Kano. The levels of Magnesium, Calcium, Manganese, Iron, Copper and Zinc were determined using atomic absorption spectrophotometer (AAS), and that of Sodium and Potassium were obtained using flame photometer (FES). The result of the study shows that the mean results of the mineral elements ranged from 62.50±0.55 - 84.82±0.74mg/kg sodium, 73.33±0.35 - 317±0.10mg/kg magnesium, 89.22±0.26 - 193.33±0.19mg/kg potassium, 70.00±0.52 - 186.67±0.29mg/kg calcium, 1.00±0.11 - 20.50±1.30mg/kg manganese, 25.00±0.11 - 80.50±0.36mg/kg iron. 4.00±0.08 - 13.00±0.24mg/kg copper and 15.00±0.34 - 50.50±0.24 zinc. There was significant difference (p < 0.05) in levels of sodium, potassium and calcium whereas no significant difference (p > 0.05) occurs in levels of magnesium, manganese, copper and zinc. In comparison with Recommended Daily Allowances of essential and trace metals set by international standard organizations, the coarse grains analysed in this work contribute little to the provision of essential and trace elements requirements.

Keywords: mineral elements, coarse grains, staple food, Kano, Nigeria

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Authors: Muhammad Luqman, Yusuf Kurniawan

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S-Boxes is one of the linear parts of the cryptographic algorithm. The existence of S-Box in the cryptographic algorithm is needed to maintain non-linearity of the algorithm. Nowadays, modern cryptographic algorithms use an S-Box as a part of algorithm process. Despite the fact that several cryptographic algorithms today reuse theoretically secure and carefully constructed S-Boxes, there is an evaluation characteristic that can measure security properties of S-Boxes and hence the corresponding primitives. Analysis of an S-Box usually is done using manual mathematics calculation. Several S-Boxes are presented as a Truth Table without any mathematical background algorithm. Then, it’s rather difficult to determine the strength of Truth Table S-Box without a mathematical algorithm. A comprehensive analysis should be applied to the Truth Table S-Box to determine the characteristic. Several important characteristics should be owned by the S-Boxes, they are Nonlinearity, Balancedness, Algebraic degree, LAT, DAT, differential delta uniformity, correlation immunity and global avalanche criterion. Then, a comprehensive tool will be present to automatically calculate the characteristics of S-Boxes and determine the strength of S-Box. Comprehensive analysis is done on a deterministic process to produce a sequence of S-Boxes characteristic and give advice for a better S-Box construction.

Keywords: cryptographic properties, Truth Table S-Boxes, S-Boxes characteristic, deterministic process

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Authors: Doaa Abbas Zaher

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For the past two decades demand for knowledge has been increasing. Management of society’s knowledge has far reaching effects to economic growth through increased capacity to complete viable activities. Organizations use information technology to effect organizational change. This is a challenge for the less developed nations whose capacity to integrate knowledge in core functions is limited. This creates organizational problems as there is global competition amongst organizations. Cross-cultural perceptions influence difference knowledge Management. This study provides a cross-cultural analysis on the influence in knowledge culture in Japan and Saudi Arabia to effect change in organizations. Since different countries adopt different knowledge management strategies, this dictates the state of organizational development through enriched organizational culture. The research uses a mixed approach design to collect data from primary and secondary sources. Primary source will use the questionnaires while secondary sources uses case analysis from books, articles, reports, and journals. The study will take a period of three years to come up with a complete paper.

Keywords: knowledge management, organizational culture, information, society knowledge

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Authors: Ji Chen, Chunhui Zhang, Fanming Zeng, Lei Zhang, Ying Li, Wei Zhang

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Based on the synthetic principle of force, a pre-compressed nonlinear isolator with quasi-zero-stiffness (QZS) is developed for shock isolation of ship equipment. The proposed isolator consists of a vertical spring with positive stiffness and several lateral springs with negative stiffness. An analytical expression of vertical stiffness of the nonlinear isolator is derived and numerical simulation on the effect of the geometric design parameters is carried out. Besides, a pre-compressed QZS shock isolation system model is established. The stiffness characteristic of the system is studied and the effects of excitation amplitude and friction damping on shock isolation performance are discussed respectively. The research results show that in comparison with linear shock isolation system, the pre-compressed QZS shock isolation system could realize constant-force or approximately constant-force function and perform better anti-impact performance.

Keywords: quasi-zero-stiffness, constant-force, pre-compressed, large deformation, shock isolation, friction damping

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Authors: Shima Soltanzadeh, Mohammad Hosain Fazel Zarandi, Mojtaba Barzegar Astanjin

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Diagnosis of male infertility by the laboratory tests is expensive and, sometimes it is intolerable for patients. Filling out the questionnaire and then using classification method can be the first step in decision-making process, so only in the cases with a high probability of infertility we can use the laboratory tests. In this paper, we evaluated the performance of four classification methods including naive Bayesian, neural network, logistic regression and fuzzy c-means clustering as a classification, in the diagnosis of male infertility due to environmental factors. Since the data are unbalanced, the ROC curves are most suitable method for the comparison. In this paper, we also have selected the more important features using a filtering method and examined the impact of this feature reduction on the performance of each methods; generally, most of the methods had better performance after applying the filter. We have showed that using fuzzy c-means clustering as a classification has a good performance according to the ROC curves and its performance is comparable to other classification methods like logistic regression.

Keywords: classification, fuzzy c-means, logistic regression, Naive Bayesian, neural network, ROC curve

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Authors: A. Lashkari, H. Khalafi, H. Khazeminejad, S. Khakshourniya

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In this paper, a numerical model is presented. The model is used to analyze a steady state thermo-hydraulic and reactivity insertion transient in TRR reference cores respectively. The model predictions are compared with the experiments and PARET code results. The model uses the piecewise constant and lumped parameter methods for the coupled point kinetics and thermal-hydraulics modules respectively. The advantages of the piecewise constant method are simplicity, efficiency and accuracy. A main criterion on the applicability range of this model is that the exit coolant temperature remains below the saturation temperature, i.e. no bulk boiling occurs in the core. The calculation values of power and coolant temperature, in steady state and positive reactivity insertion scenario, are in good agreement with the experiment values. However, the model is a useful tool for the transient analysis of most research reactor encountered in practice. The main objective of this work is using simple calculation methods and benchmarking them with experimental data. This model can be used for training proposes.

Keywords: thermal-hydraulic, research reactor, reactivity insertion, numerical modeling

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Authors: Wullapa Wongsinlatam

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Back propagation algorithm (BP) is a widely used technique in artificial neural network and has been used as a tool for solving the time series problems, such as decreasing training time, maximizing the ability to fall into local minima, and optimizing sensitivity of the initial weights and bias. This paper proposes an improvement of a BP technique which is called IM-COH algorithm (IM-COH). By combining IM-COH algorithm with cuckoo search algorithm (CS), the result is cuckoo search improved control output hidden layer algorithm (CS-IM-COH). This new algorithm has a better ability in optimizing sensitivity of the initial weights and bias than the original BP algorithm. In this research, the algorithm of CS-IM-COH is compared with the original BP, the IM-COH, and the original BP with CS (CS-BP). Furthermore, the selected benchmarks, four time series samples, are shown in this research for illustration. The research shows that the CS-IM-COH algorithm give the best forecasting results compared with the selected samples.

Keywords: artificial neural networks, back propagation algorithm, time series, local minima problem, metaheuristic optimization

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Authors: Ibrahim Alhumaidan

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As King Saud University believes in the critical role played by technology and its effectiveness in achieving quality, speed of achievement, facilitating follow-up and enhancing responsibility undertaking; the university is keen on activating its e-services for the purpose of attaining the primary requirements of achievement and perfection. The web portal of the student's academic system comes as one of the most important practices in technological and e-transaction aspects. It enables students to carry out their processes–registration, addition, evaluation, viewing their results, and scholastic accomplishments, etc.– through the relevant web portal. The aim of this study is to recognize Education College students' attitude -as one of King's University Colleges- regarding the usage of the academic system web portal, its effectiveness in saving time and effort, and, efficiency in enhancing student's planning skills. The study society is all students of college of education in King Saud University and the sample has been chosen randomly from them. The study tool is a questionnaire designed to learn about students' views about using the web portal; as the researcher used the surveying methodology to achieve the aim of the study.

Keywords: web portal, academic system, education faculty, students, planning skills

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Authors: Saeed Dehnavi, Zahra Hadadi, Marzieh Rezabeigi, Nader Monirpoor

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This study has been performed with the goal of investigating the effectiveness of psychodrama in the reduction of social anxiety among the male adolescents in Kermanshah. 210 adolescents (13-14 year-olds) from four junior high schools in Kermanshah filled Liebowitz Social Anxiety Scale for Children and Adolescents (LSAS-CA) (Masia-Warner, Klien & Liebowitz, 2003). 30 of the adolescents who obtained the highest scores in LSAS-CA scale were chosen as the sample and were randomly assigned as experimental group (15 people) and control group (15 people). The experimental group participated in two-hour sessions of psychodrama twice a week for 6 weeks. The control group received no intervention. The findings of this study showed a significant reduction in the symptoms of social anxiety among the adolescents in experimental group in comparison to that of the control group. Also a three-month follow-up confirmed the stability of the results. Adolescents’ interactions in the psychodrama group, talking about their problems to the group, and achieving appropriate solutions by themselves are the useful factors of this intervention.

Keywords: psychodrama, social anxiety disorder, adolescents, male adolescents

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Authors: Nyumbaiza Tambwe

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The purpose of this paper is to demonstrate that hybrid urban agriculture as the most practiced type of urban agriculture in the majority of cities in sub-Saharan Africa can be taken as an alternative strategy in fighting food insecurity. The practice not only provides food, generates income and fights against unemployment; it constitutes a true back-up for households during crisis linked to the nature of capitalism system. African cities are mostly characterized by rapid population growth, rampant poverty, and high level of unemployment and food insecurity. Those factors and many others are at the origin of the emergence of urban agriculture in many African cities. Based particularly on results of research undertaken in the Democratic Republic of Congo (DRC), but also in comparison with those realized in other parts of the African continent, the paper is a case study. Therefore, the paper firstly describes the situation of food in Africa, secondly, presents hybrid urban agriculture as a household strategy in fighting food insecurity and finally shows possibilities and limits of this practice.

Keywords: alternative strategy, food security, household strategy, hybrid urban agriculture

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Authors: H. Kazemi Esfeh, V. Akbari, M. Ehdaei, T. N. G. Borhani, A. Shamiri, M. Najafi

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In an industrial fluidized bed polymerization reactor, particle size distribution (PSD) plays a significant role in the reactor efficiency evaluation. The computational fluid dynamic (CFD) models coupled with population balance equation (CFD-PBM) have been extensively employed to investigate the flow behavior in the poly-disperse multiphase fluidized bed reactors (FBRs) utilizing ANSYS Fluent code. In this study, an existing CFD-PBM/ DQMOM coupled modeling framework has been used to highlight its potential to analyze the industrial-scale gas phase polymerization reactor. The predicted results reveal an acceptable agreement with the observed industrial data in terms of pressure drop and bed height. The simulated results also indicate that the higher particle growth rate can be achieved for bigger particles. Hence, the 2D CFD-PBM/DQMOM coupled model can be used as a reliable tool for analyzing and improving the design and operation of the gas phase polymerization FBRs.

Keywords: computational fluid dynamics, population balance equation, fluidized bed polymerization reactor, direct quadrature method of moments

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Authors: Krishna Mohana Rao Gurram, R. Padmini, P. Vamsi Krishna

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As a part of extensive research for ecologically safe and operator friendly cutting fluids, this paper presents the experimental investigations on the performance of eco-friendly vegetable oil based nanofluids in turning operation. In order to assess the quality of nano cutting fluids used during machining, cutting temperatures, cutting forces and surface roughness under constant cutting conditions are measured. The influence of two types of nanofluids prepared from nano boric acid and CNT particles mixed separately with coconut oil, on machining performance during turning operation is examined. Comparative analysis of the results obtained is done under dry and lubricant environments. Results obtained using cutting fluids prepared from vegetable oil based nanofluids are encouraging and more pronouncing by the application of CCCNT at machining zone. The extent of improvement in reduction of cutting temperatures, main cutting force, tool wear and surface roughness is tracked to be 13%, 37.5%, 44% and 40% respectively by the application of CCCNT compared to dry machining.

Keywords: nanoparticles, vegetable oil, machining, MQL, surface roughness

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Authors: K. Bourouni, M. Chacha, T. Jaber, A. Tchantchane

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In Multi-Effect Distillation (MED) desalination evaporators, the scale deposit outside the tubes presents a barrier to heat transfers reducing the global heat transfer coefficient and causing a decrease in water production; hence a loss of efficiency and an increase in operating and maintenance costs. Scale removal (by acid cleaning) is the main maintenance operation and constitutes the major reason for periodic plant shutdowns. A better understanding of scale deposition mechanisms will lead to an accurate determination of the variation of scale thickness around the tubes and an improved accuracy of the overall heat transfer coefficient calculation. In this paper, a coupled heat transfer-calcium carbonate scale deposition model on a horizontal tube bundle is presented. The developed tool is used to determine precisely the heat transfer area leading to a significant cost reduction for a given water production capacity. Simulations are carried to investigate the influence of different parameters such as water salinity, temperature, etc. on the heat transfer.

Keywords: multi-effect-evaporator, scale deposition, water desalination, heat transfer coefficient

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Authors: Vincent King Soon Wong, Hong Seng Ng, Florinna Sim

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Negative Bias Temperature Instability (NBTI) is one of the critical degradation mechanisms in semiconductor device reliability that causes shift in the threshold voltage (Vth). However, thorough understanding of this reliability failure mechanism is still unachievable due to a recovery characteristic known as NBTI recovery. This paper will demonstrate the severity of NBTI recovery as well as one of the effective methods used to mitigate, which is the minimization of measurement system delays. Comparison was done in between two measurement systems that have significant differences in measurement delays to show how NBTI recovery causes result deviations and how fast measurement systems can mitigate NBTI recovery. Another method to minimize NBTI recovery without the influence of measurement system known as Fast Wafer Level Reliability (FWLR) NBTI was also done to be used as reference.

Keywords: fast vs slow BTI, fast wafer level reliability (FWLR), negative bias temperature instability (NBTI), NBTI measurement system, metal-oxide-semiconductor field-effect transistor (MOSFET), NBTI recovery, reliability

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Authors: A. L. Qureshi, A. A. Mahessar, A. Baloch

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Flood wave propagation in river channel flow can be enunciated by nonlinear equations of motion for unsteady flow. However, it is difficult to find analytical solution of these complex non-linear equations. Hence, verification of the numerical model should be carried out against field data and numerical predictions. This paper presents the verification of developed finite element model applying for unsteady flow in the open channels. The results of a proposed model indicate a good matching with both Preissmann scheme and HEC-RAS model for a river reach of 29 km at both sites (15 km from upstream and at downstream end) for discharge hydrographs. It also has an agreeable comparison with the Preissemann scheme for the flow depth (stage) hydrographs. The proposed model has also been applying to forecast daily discharges at 400 km downstream from Sukkur barrage, which demonstrates accurate model predictions with observed daily discharges. Hence, this model may be utilized for predicting and issuing flood warnings about flood hazardous in advance.

Keywords: finite element method, Preissmann scheme, HEC-RAS, flood forecasting, Indus river

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Authors: Seyed Abolhasan Naeini, Saeideh Mohammadi

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Rapid urban development leads to the construction of urban tunnels for transport. Passage of tunnels under the surface structures and utilities prompted the changes in the site conditions and hence alteration of the dynamic response of surface structures. Therefore, in this study, the effect of the interaction of tunnel-superstructure on the site response is investigated numerically. For this purpose, Fast Lagrangian Analysis of Continua (FLAC 2D) is used, and stratification and properties of soil layers are selected based on the line No 7 of Tehran subway. The superstructure is modeled both as an equivalent surcharge and the actual structure, and the results are compared. A comparison of the results shows that consideration of structure geometry is necessary for dynamic analysis and it leads to the changes in displacements and accelerations. Consequently, the geometry of the superstructure should be modeled completely instead of the application of an equivalent load. The effect of tunnel diameter and depth on the settlement of superstructures is also studied. Results show that when the tunnel depth and diameter grow, the settlements increase considerably.

Keywords: tunnel, FLAC2D, settlement, dynamic analysis

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Authors: Farshid Hajati, Soheila Gheisari, Ali Cheraghian, Yongsheng Gao

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This paper presents a new Surface Geodesic Derivative Pattern (SGDP) for matching textured deformable 3D surfaces. SGDP encodes micro-pattern features based on local surface higher-order derivative variation. It extracts local information by encoding various distinctive textural relationships contained in a geodesic neighborhood, hence fusing texture and range information of a surface at the data level. Geodesic texture rings are encoded into local patterns for similarity measurement between non-rigid 3D surfaces. The performance of the proposed method is evaluated extensively on the Bosphorus and FRGC v2 face databases. Compared to existing benchmarks, experimental results show the effectiveness and superiority of combining the texture and 3D shape data at the earliest level in recognizing typical deformable faces under expression, illumination, and pose variations.

Keywords: 3D face recognition, pose, expression, surface matching, texture

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Authors: Seo Soo-Yeon, Kim Sang-Ku, Noh Sang-Hyun, Lee Ji-Eun, Kim Seol-Ki, Lim Jong-Wook

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This paper presents a test result to find the structural capacity of Hollow-Precast Concrete (HPC) column with Head-Splice Sleeve (HSS) for the connection of bars under horizontal cyclic load. Two Half-scaled HPC column specimens were made with the consideration of construction process in site. The difference between the HPC specimens is the location of HSS for bar connection. The location of the first one is on the bottom slab or foundation while the other is above the bottom slab or foundation. Reinforced concrete (RC) column was also made for the comparison. In order to evaluate the hysteretic behavior of the specimens, horizontal cyclic load was applied to the top of specimen under constant axial load. From the test, it is confirmed that the HPC columns with HSS have enough structural capacity that can be emulated to RC column. This means that the HPC column with HSS can be used in the moment resisting frame system.

Keywords: structural capacity, hollow-precast concrete column, head-splice sleeve, horizontal cyclic load

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Authors: Samuel Olugbenga King

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Using a reflective analysis tool to provide both local and global perspectives, this study focuses on the longitudinal evaluation of the Graduate Student Development (GSD) initiative, the Preparing Future Faculty (PFF) program. The reflection process involves examining the past and present to identify challenges, and culminates in the creation of an action plan to address barriers to further growth and teaching development of graduate students, thus positively impacting student experience. The outcomes of the reflective critique of the PFF program indicate that lack of mentoring as well as inadequate feedback and funding are barriers that need to be addressed to positively impact the graduate student experience. Consequently, interventions, such as peer and student evaluations, and alumni surveys are highlighted as pragmatic modes of addressing the inadequate feedback and mentoring barriers. However, funding remains an ongoing challenge. This article is a contribution to the literature on the use of critical reflection approaches to investigate and evaluate specific programming that focuses on enhancing the graduate student experience and development.

Keywords: graduate student experience, longitudinal reflection, quality enhancement, teaching

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Authors: Pattaramon Pongjetpong

Abstract:

In recent years, infectious diseases have increased considerably, and they are amongst the most common leading causes of death all over the world. Several medicinal plants are well known to contain active constituents such as flavonoids, carotenoids, and phenolic compounds, which are plausible candidates for therapeutic purposes. This study aimed to examine the antimicrobial activities of M. cochinchinensis and P. kesiya extracts using the agar disk diffusion method and broth microdilution to determine the minimum inhibitory concentration (MIC) value. In this study, Momordica cochinchinensis and Pinus kesiya extracts are investigated for antibacterial activity against Staphylococcus aureus. The results showed that S. aureus was susceptible to P. kesiya extracts with an MIC value of 62.5 µg/ml, while M. cochinchinensis showed MIC against S. aureus was greater than 2000 µg/ml. In summary, P. kesiya extract showed potent antibacterial activity against S. aureus, which could greatly value developing as adjuvant therapy for infectious diseases. However, further investigation regarding purification of the active constituents as well as a determination of the mechanism of antimicrobial action of P. kesiya active compound should be performed to identify the molecular target of the active compounds.

Keywords: antimicrobial activity, Momordica cochinchinensis, Pinus kesiya, Staphylococcus aureus

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